1. Field of the Invention
This invention relates generally to ergonomic weight support devices, for seats.
2. Related Art
Lumbar supports and head rests for seats, particularly automobile seats, are known. See U.S. Pat. Nos. 5,050,930; 5,397,164; 5,498,063; 5,626,390; 5,775,773; 6,003,941; 4,354,709; 4,452,485; 4,632,454; 4,880,271; GB 2013 487A and D 169 293 B1. These devices all have in common one or more flexible members that may be flexed in order to create a convex surface with its apex towards the lumbar spine of a human being sitting in the seat into which the device is incorporated. This convex flexion is induced by any of a great variety of means for compression, See, e.g., U.S. Pat. No. 4,354,709 or tension, See, e.g., U.S. Pat. No. 5,498,063. It is universal among these prior art lumbar supports that both an upper extremity of the convex pressure element and the lower extremity of it are anchored to a framework within the seat. These upper and lower elements may be fixedly anchored or movably anchored, or a combination of the two, so long as they may be pressured to move closer together to project the apex of the convexity farther out from the plane of the seat for greater lumbar support and conversely may have pressure released in order to move the apex of the convexity closer to the plane of the seat for less lumbar support.
Whether the pressure producing a greater or lesser convexity is produced by compression or tension, all prior art lumbar support devices have required the use of plurality of moving parts, many of which are under dynamic tension for actuation of the convexity, and again under dynamic tension for supporting the weight of the seat passenger. The multiplicity of moving parts in prior art lumbar supports complicates manufacture, increases expense of materials necessary, increases the likelihood of component failure and shortens the life span of the devices.
Moreover, prior art lumbar supports require a relatively large amount of space to, accommodate the relatively cumbersome tensioning or compression apparatuses, together with the frameworks necessary for their support. Accordingly, prior art devices are generally limited in their applications in that it is difficult to convert their component orientation for support of other parts of the human body in a seat, as, for example, the head and neck or the thighs.
As seat designs are modified to incorporate more comfort devices, such as duct work for heating and cooling, the amount of space available inside seats for lumbar support devices shrinks. There is need for smaller lumbar supports.
There is a need in the art for a universal ergonomic support which occupies less space, costs less to manufacture and install, simplifies manufacture, decreases needed components, uses a more robust mechanism for supporting the weight of a human passenger and/or may be more universally used for lumbar, head and neck and thigh support as well as only lumbar support.